condition mean min max ZT0-3 0.32053866666666664 0.19395400000000002 0.41983899999999996 ZT4-7 0.46265 0.46265 0.46265 ZT8-11 0.2908415 0.2908415 0.2908415 ZT12-15 0.27493825 0.21529399999999999 0.3345825 ZT16-19 0.141621 0.141621 0.141621 ZT20-23 0.3627125 0.3627125 0.3627125